I don't know he didn't seem that bad when The blue haired talked to him
Oh yeah, his inferiority complex is going to kick into hyperdrive now that they are in close quarters and have chances to actually meet up. I expect him to try and steal the boyfriend and when that fails try to destroy their relationship through any means possible. Hopefully he realizes his worth is not defined by whether or not his brother is happy before he gets to the stabby stage, lol.
I really hope what you said happens that will be really interesting ε=ε=(ノ≧∇≦)ノ
I have a really bad feeling that the brother is going to do something like really bad.#－.－)